Only Arches Watercolor papers contain animal gelatin. This is due to the process of sizing.

The watercolor papers are internally sized with either starch or synthetics while on the machine. As the paper comes off of the machine it is hit with the animal gelatin for the external sizing that is necessary for watercolor papers. Keep in mind when we say machine, we are talking about a mouldmade sheet and not a machine made sheet.

The Arches Printmaking papers are only internally sized and therefore do not contain nor require animal gelatin.